1. Field of the Invention
The present invention relates to a differential device applied to conveyance means such as automobiles, differential motion of which is controllable and detectable from the exterior thereof.
2. Description of the Related Art
As is known, an automobile is equipped with a differential to distribute a driving force of an engine to right and left output axles. The differential allows a differential motion between the axles and hence right and left wheels can maintain traction with the road while the automobile is turning.
To provide a driver with operability for temporary lock of the differential motion, a so-called “Lock-up Differential” is used. The lock-up differential in general has a clutch for locking the differential motion and an actuator for actuating the clutch under control by the driver. The lock-up differential may be required to be equipped with a means for canceling the lock of the differential motion and another means for detecting whether the differential motion is locked or freed.
Installing the clutch and these means in a casing of the differential leads to complexity of a structure and inaccessibility to these elements. These are considerable disadvantages on occasions of assembly, maintenance and repair.